Lane maintenance machine suitable for battery operation

ABSTRACT

A bowling lane maintenance machine has its operating functions designed and controlled in such a manner that the machine may be battery-operated without loss of performance. Included in the operation are special movements of the machine at the pin deck to flick moisture off blades of the squeegee assembly and limited activation of the vacuum motor to reduce battery drain.

RELATED APPLICATIONS

This is a divisional application of U.S. application Ser. No. 11/424,027filed Jun. 14, 2006, the entire disclosure of which is incorporatedherein by reference.

TECHNICAL FIELD

The present invention relates to the field of bowling lane maintenancemachines, in particular, to machines that can both clean and dress thelanes as they move along the surface thereof. It relates especially to amachine whose various operating functions are carried out in such amanner as to render the machine suitable for, but not necessarilylimited to, battery operation so as to eliminate the need for anelectrical supply cord connecting the machine to a source of electricalhouse current.

BACKGROUND AND SUMMARY

It is well known in the prior art to provide a lane machine that appliescleaning liquid to the lane at the front of the machine, picks up theliquid, surface grime and old dressing (oil) near the middle of themachine, and then applies a new film of oil to the cleaned surface atthe rear of the machine as the machine is traveling along the length ofthe lane. In the past, such machines have required connection to housecurrent through a long, unwieldy supply cord because the sequence ofoperations performed by the machine drew too much electrical current tomake battery operation practical considering the significant number oflanes in a bowling facility.

In a machine constructed in accordance with the principles of thepresent invention the operational steps of the machine are such thatbattery operation can become a practical reality, without sacrificingquality and speed. Although the inventive operating steps are beneficialeven if not incorporated into a machine that is battery-powered, theconvenience of battery operation makes incorporating these principlesinto a battery-powered machine particularly attractive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a left front perspective view of a maintenance machineembodying the principles of the present invention with its top coverremoved to reveal internal details of construction;

FIG. 2 is a right rear perspective view of the machine;

FIG. 3 is a right front perspective illustration of certain internalcomponents of the machine with walls and other structures removed forclarity;

FIG. 4 is a left rear perspective illustration of certain internalcomponents of the machine with walls and other structures removed forclarity;

FIG. 5 is a right side elevational view of the machine with the nearsidewall thereof removed to reveal internal details of construction;

FIG. 6 is an enlarged, fragmentary right side elevational view of themachine illustrating the action of the squeegee blades as they engagethe lane during forward travel of the machine;

FIG. 7 is an enlarged, fragmentary right side elevational view of themachine similar to FIG. 6 but illustrating the machine stopped at theend of its forward travel with the squeegee assembly passed beyond andoverhanging the edge of the pin deck to flip moisture off the squeegeeassembly;

FIG. 8 is an enlarged, fragmentary right side elevational view of themachine similar to FIG. 6 but illustrating the squeegee assembly in araised position; and

FIGS. 9-13 are block diagrams of the different portions of theelectrical system of the machine.

DETAILED DESCRIPTION

The present invention is susceptible of embodiment in many differentforms. While the drawings illustrate and the specification describescertain preferred embodiments of the invention, it is to be understoodthat such disclosure is by way of example only. There is no intent tolimit the principles of the present invention to the particulardisclosed embodiments.

The machine 10 illustrated in the drawings is similar in many respectsto the machine disclosed in U.S. Pat. No. 5,729,855 and U.S. Pat. No.6,939,404. Accordingly, the '855 and '404 patents are herebyincorporated by reference into the present specification. In view of thefull disclosure in the '855 and '404 patents of the construction andoperation of the lane machine, the construction and operation of themachine 10 will be described only generally herein.

The machine 10 has a cleaning system denoted broadly by the numeral 12and located generally in the front of the machine. A dressing(preferably oil) application system is denoted broadly by the numeral 14and located generally in the rear portion of the machine. These twosystems perform their functions as the machine is propelled down thelane and back by lane-engaging drive wheels 16 and 18 fixed to atransverse shaft 20 that is powered by a drive motor 22 (Baldor 24 VDCmodel 24A531Z019G1) and a chain and sprocket assembly 24. A conventionalproximity sensor speed tachometer 25 (FIG. 9) is coupled with the end ofdrive shaft 20.

The oil application system 14 includes an applicator roll 26(hereinafter sometimes referred to as the “buffer”) disposed forengaging the lane surface, a reciprocating oil dispensing head 28 thattravels back and forth across the width of the lane above buffer 26, anda brush assembly 30 between buffer 26 and dispensing head 28 forreceiving oil from head 28 and delivering it to buffer 26. Buffer 26 isrotatably driven by a buffer motor 31 (Baldor 24 VDC model 24A532Z046G1)(FIG. 10). Buffer 26 pivots up and down, in and out of contact with thebowling lane surface by way of linkage 27 operated by a buffer up/downmotor 29 (Merkle Korff 31 RPM 24 VDC model S-3727-87D) (FIG. 12). In thedown position, buffer 26 operates a buffer down limit switch 21 andoperates a buffer up limit switch 23 in the up position.

Details of the construction and manner of use of brush assembly 30 aredisclosed in U.S. Pat. No. 7,056,384 titled “Strip Brush Bowling LaneDressing Application Mechanism”, which is hereby incorporated byreference herein. Oil application system 14 additionally includes areservoir 32, a positive displacement pump (not shown) (FMI model RHOCKCLab Pump Jr.) having a motor 33 (FIG. 10) (Dayton 24 VDC model3XE19) forsupplying oil from reservoir 32 to dispensing head 28, and a three-wayvalve 35 (FIG. 9) for controlling the flow of oil. In a recycle positionvalve 35 recycles oil back to reservoir 32, and in a delivery positionvalve 35 delivers oil from pump 33 to dispensing head 28.

Oil dispensing head 28 is mounted for reciprocation along a transverseguide track 34 extending between the sidewalls of the machine. Anendless drive belt 36 is secured to head 28 and has its opposite endslooped around a pair of pulleys 38 and 40, the pulley 40 being operablycoupled with a reversible motor 42 (Crouzet 24 VDC model 808050Y07.66Z)to provide driving power to belt 36 and thus propel dispensing head 28along track 34. A pair of left and right sensors in the form ofproximity switches 44 and 46 adjacent opposite ends of the path ofreciprocal travel of dispensing head 28 are operable to sense thepresence of dispensing head 28 as it reaches the limits of its path oftravel so as to signal the motor 42 to reverse directions and drivedispensing head 28 in the opposite direction along track 34.

The pulley 38 is fixed to a long fore-and-aft extending shaft 48disposed just outboard of the right sidewall of the machine. Near itsrear end, just forwardly of pulley 38, shaft 48 is provided with anotched wheel 50 whose rotation is sensed by a sensor 52. An output fromsensor 52 is sent to the control system of the machine (described inmore detail below) for the purpose of determining the precise locationof the oil dispensing head 28 across the width of the machine and thebowling lane. Such location is coordinated with a particular lane oilpattern that has been programmed into the control system of the machineso that oil dispensing head 28 may be actuated to precisely dispense oilat predetermined locations along its path of reciprocation.

Distance down the lane is determined by a pair of lane-engaging wheels53 (FIGS. 3, 4 and 5) located just in front of the rear wall of themachine. Wheels 53 are fixed to a common cross shaft 54 that rotates anotched wheel 55 (FIG. 4) via a chain drive 56 (FIG. 3). The number ofrevolutions of notched wheel 55 is detected by a sensor 57 (FIG. 4) thatsends a signal to the control system of the machine.

The cleaning system 12 includes one or more cleaning liquid dispensingheads 58 that reciprocate across the path of travel of the machine as itmoves along the lane. While system 12 may also include one or morepressurized spray nozzles as in conventional machines, in a preferredembodiment no such conventional spray nozzles are utilized. In theparticular embodiment disclosed herein, only a single dispensing head 58is utilized, such head 58 traveling essentially the full transversewidth of the machine to the same extent as the oil dispensing head 28.

Dispensing head 58 includes a vertically disposed, depending dischargetube 60 provided with a tip 62 that is located close to the lanesurface. In one form of the invention, tip 62 is not in the nature of anatomizing nozzle but is instead configured and arranged to emit liquidin a fairly coherent stream so that a bead of cleaning liquid is laiddown on the lane surface. One suitable tip 62 for carrying out thisparticular non-atomizing function is available from the Value PlasticsCompany of Fort Collins, Colo. as part number VP S5401001N. Other typesof tips (not shown) that atomize, breakup or diffuse liquid supplied tothe tip may also be utilized where broader surface area coverage by thecleaning liquid is desired. In either case, tip 62 is preferablyprovided with an internal check valve (not shown).

Cleaning system 12 further includes a guide track 64 attached to thefront wall of machine 10 that slidably supports dispensing head 58 forits reciprocal movement. Track 64 extends across substantially theentire width of machine 10 to the same extent as the track 34 associatedwith oil dispensing head 28. An endless drive belt 66 is attached todispensing head 58 for providing reciprocal drive thereto, the belt 66at its opposite ends being looped around a pair of pulley wheels 68 and70 respectively.

Although pulley 68 may be driven in a number of different ways,including by its own separate drive motor, in a preferred form of theinvention pulley 68 is fixed to the forwardmost end of shaft 48 frompulley 38 so that both dispensing heads 28 and 58 are driven by the samereversible motor 42. Consequently, both oil dispensing head 28 andcleaning liquid dispensing head 58 are reciprocated simultaneously bymotor 42 when the latter is actuated. However, it will be noted that oildispensing head 28 and cleaning liquid dispensing head 58 reciprocate inmutually opposite directions due to the fact that oil dispensing head 28is secured to the upper run 36 a of its drive belt 36 while cleaningliquid dispensing head 58 is secured to the lower run 66 b of its drivebelt 66.

Cleaning system 12 further includes a cleaning solution reservoir 72 atthe rear of machine 10. A supply line 74 leading from reservoir 72 iscoupled in flow communication with a reversible peristaltic pump 76(Barnant 24 VDC model D-3138-0009). An outlet line 80 from pump 76 leadsto discharge tube 60 of dispensing head 58 for supplying cleaning liquidto head 58. A cleaner control 82 (FIGS. 10 and 11) is electricallyconnected to cleaner pump 76 for adjusting the speed of pump 76, andthus the amount of cleaner discharged by head 58.

Because pump 76 is preferably a peristaltic pump, it supplies liquid todispensing head 58 in constant volume slugs or squirts that enable thecleaning liquid to be very precisely and accurately metered onto thelane surface. Furthermore, it permits the supply of liquid to dispensinghead 58 to be essentially instantaneously stopped and started, which, inconjunction with the control valve, affords precise, board-by-boardcontrol over the pattern of cleaning liquid applied to the lane surfaceby dispensing head 58.

Cleaning system 12 additionally includes a wiping assembly 88immediately behind cleaning liquid dispensing head 58. Assembly 88includes a web 90 of soft material such as duster cloth looped around alower compressible back-up member 92 in the nature of a roller thatextends across the full width of the machine. Cloth 90 is stored on aroll 94 and is paid out at intervals selected by the operator and takenup by a takeup roll 96. Wiping assembly 88 is similar in principle tothe corresponding wiping assembly disclosed in U.S. Pat. No. 6,615,434,which patent is hereby incorporated by reference into the presentspecification. A duster unwind motor 95 (FIG. 12) (Merkle Korff 9 RPM 24VDC S-3828-87D) is coupled with roll 94 and, when activated, rotatesroll 94 to let out slack in the cloth, allowing backup member 92 togravity to the lane surface. A duster windup motor 97 (FIG. 12) (MerkleKorff 9 RPM 24 VDC S-3828-87D) is coupled with takeup roll 96 and, whenactivated, rotates roll 96 to raise backup member 92 off the lanesurface.

A further component of cleaning system 12 comprises a vacuum pickup head98 located behind wiping assembly 88. Vacuum pickup head 98 extendsessentially the full width of machine 10 and includes a squeegeeassembly 99 comprising a pair of resilient, squeegee-type blades 100 and102 that assist in picking up the thin film of cleaning liquid left onthe lane surface after the wiping assembly 88 has acted upon the liquid.Lift linkage 101 is connected to a squeegee lift motor 103 (FIG. 12)(Merkle Korff 31 RPM 24 VDC S-3727-87D) and is operably coupled withsuction head 98 and squeegee assembly 99 for moving the same between anoperating position in engagement with the lane as shown in FIGS. 5,6 and7 and a raised position out of engagement with the lane as shown in FIG.8. A large vacuum hose 104 leads from pickup head 98 to a holding tank106 for storing liquid picked up by head 98. Vacuum pressure withinholding tank 106 is obtained by means of a vacuum motor 107 (Ametek 24VDC model 116155-00) (FIG. 10) coupled with tank 106.

FIGS. 9-12 are block diagrams illustrating various portions of thecontrol system 108 of machine 10. Control system 108 includes, inaddition to the electrical components already mentioned above,controller 110 (programmable logic controller Omron model CPM2A), drivemotor control 112, printed circuit board 114, and control relays CR1,CR2, CR3, CR4, CR5, CR6, CR7, CR8, CR9, CR10, CR11, and CR12. Controlsystem 108 further includes start switch 116 (FIG. 9) and an emergencystop switch 117 (FIG. 13).

An electrical power supply system 120 for machine 10 is illustrated inFIG. 13, portions of system 120 also being visible in FIGS. 1-12. In apreferred embodiment of the invention, the heart of power system 120comprises a pair of series-connected, 12 VDC rechargeable storagebatteries 122 (EnerSys Energy Products model Odyessey PC925) thatjointly provide up to 24 volts DC power to operating components of themachine. Batteries 122 are connected to a forty amp charger 124 (Iotacharger model DLS-27-40 with IQ Smart Charge Controller) that, in turn,is connected to a receptacle 126 (FIG. 1) on the left sidewall of themachine. Receptacle 126 may be connected to a 120 VAC outlet in thebowling center using an electrical supply cord (not shown) in order torecharge batteries 122 from time-to-time, or to run the machine on 120VAC power supply. As is well understood by those skilled in the art,charger 124 converts 120 VAC power from the supply cord to 24 VDC powerfor recharging batteries 122 and/or for operating the 24 VDC operatingand control components of the machine. Preferably, a constant voltageregulator 128 (Solar Converters Inc. model CVP 12/24-15) is interposedbetween batteries 122 on the one hand and dispensing head motor 42, oilpump motor 33, buffer motor 31, three-way valve 35, and drive motor 22on the other hand to maintain constant voltage to such components.

Operation

The operation of machine 10 is controlled by way of the programmedoperating controller 110. Although machine 10 may be selectivelyoperated through appropriate switches to clean the lanes only, or to oilthe lanes only, in the following example machine 10 is operated to bothclean and oil the lanes.

Initially machine 10 is placed on the approach of a bowling lane justbehind the foul line. The operator presses start switch 116 one time,which initiates the sequence of maintenance operations. A variety oflane oil patterns can be selected by way of the key pad and display 130(FIG. 1) as is conventional. The duster unwind motor 95 comes on at thistime to dispense a new section of cloth, but if the normally opencontacts of duster up switch 134 do not open up, there will be a “dusterempty” error displayed. The squeegee assembly 99 will move down and stopwhen the normally open contacts of down switch 132 close. If the switchcontacts do not close, there will be a “squeegee did not lower” errordisplayed. The oil pump 33 also turns on.

The machine 10 is then pushed onto the lane and properly seated. Thestart switch 116 is pressed a second time and the dispensing heads motor42 will start up and cause both heads 28 and 58 to begin moving. Oildispensing head 28 moves from left to right, as the lane is viewed fromthe foul line looking toward the pin deck, while cleaner head 58 movesfrom right to left.

Cleaner pump motor 76 is energized at the same time as heads motor 42.Thus, as cleaner head 58 starts to move, it also starts to apply cleanerinstantly to the lane and does not stop until the last programmed“squirt distance” down the lane has been reached. When the oil head 28reaches the right board edge proximity switch 46, the moving heads 28,58 will reverse their directions and oil head 28 will begin to apply thefirst stream of oil.

The oiling head 28 is now moving in a right-to-left direction, whilecleaner head 58 is moving in a left-to-right direction. When oiling head28 reaches the left board edge proximity switch 44, the heads motor 42will reverse, at which time buffer motor 31 starts up and drive motor 22is energized to start the machine moving down the lane. Vacuum motor 107has remained in an “off” condition during this initial startup phase,but after machine 10 has traveled about two feet down the lane, vacuummotor 107 turns on. It is also to be noted that after start switch 116has been pressed a second time, machine 10 will start a clock (notshown) to record the total amount of run time on the display 130. Thetotal amount of time the three-way valve 35 dispenses oil for each laneis also shown in the display 130.

As machine 10 travels forward down the lane, the oiling and cleaningheads 28, 58 continue to operate, applying oil and cleaner. Theboard-counting sensor 52 monitors the positions of the moving heads 28,58. If the motion is interrupted, an error message will be displayed.

During movement of the machine 10 down the lane, the lane distancesensor 57 counts inches traveled and monitors movement of the machine.If travel is interrupted, an error message will be displayed. The speedof machine 10 is also being monitored by the speed tack 25 and isdisplayed continuously. As the machine continues to move forward, speedswill change (through a drive motor speed control (KB model KBBC-24)) andoil and cleaner will continue to be dispensed to the lane as programmed.As the machine approaches the applied oil distance in accordance withthe selected program, the oil pump motor 33 turns off but the buffermotor 31 stays on so buffer 26 continues to buff oil onto the lane.

When the oil distance is reached, buffer 26 stops and buffer lift motor29 is energized to raise buffer 26 off the lane until buffer up limitswitch 23 is operated. If the contacts for raising buffer 26 do notclose, there will be an error message displayed. If the up switch 23sticks closed when it should be open, a “brush down” error message willbe displayed.

Additionally, when the oil distance has been reached machine 10 willshift into high speed and continue to travel toward the pin deck. As themachine approaches the pin deck, the programmed distance for theapplication of cleaner will be reached, causing cleaner pump motor 76 tobe turned off and heads motor 42 to be deenergized so as to stopmovement of dispensing heads 28, 58. At the same time the machine willdown-shift to low speed to reduce its momentum into the pin deck.

When machine 10 enters the pin deck, the duster windup motor 97 willturn on and start to windup the cloth to raise the backup member 92. Thenormally open contacts of the duster up switch 134 will close to turnoff the duster windup motor 97. If the contacts do not close, there willbe a “duster did not wind up” error message displayed.

Machine 10 then continues the rest of its travel with squeegee assembly99 engaging the lane in the manner illustrated in FIG. 6 before comingto a stop at a point where the front of the machine, including squeegeeassembly 99, travels off and overhangs the edge 136 of the pin deck 138as illustrated in FIG. 7. Drive motor 50 has been shut off. This allowsthe resilient blades 100, 102 of squeegee assembly 99, which have beenflexed rearwardly as the machine travels forwardly down the lane, toflip resiliently forwardly in a quick snapping action and throw offcleaning liquid moisture that may otherwise cling to the blades.Squeegee lift motor 103 is then activated to lift squeegee assembly 99and suction head 98 into a raised position as illustrated in FIG. 8.Squeegee lift motor 103 stops when the normally open contacts of thesqueegee up limit switch 136 close. If the contacts do not close, anerror message will be displayed.

Drive motor 50 is then driven in reverse for a short duration, causingmachine 10 to move in the reverse direction toward the foul line andstop after moving four inches. The squeegee assembly 99 and suction head98 are then lowered to re-engage the blades 100, 102 with the pin deck138. Drive motor 50 is then driven in forward to advance the machineforwardly four inches, whereupon it stops to once again cause squeegeeassembly 99 to overhang the edge 136 of pin deck 138. Blades 100, 102snap forwardly to flip off any excess moisture. The squeegee assembly 99then lifts.

Drive motor 50 now reverses to cause machine 10 to move in the reversedirection toward the foul line at high speed. At the same time vacuummotor 107 is turned off and cleaner pump motor 76 is run in reverse forone second to help reduce the possibility of dripping cleaner out of tip62 of the cleaner head 58.

As machine 10 travels in reverse, the lane distance sensor 57 countsinches traveled and continuously monitors movement of the machine. Iftravel is interrupted, an error message will be displayed. As themachine reaches the oil distance, buffer 26 begins to lower and stops inits down position when the normally open contacts of the buffer downswitch 21 close. If the contacts do not close, an error message isdisplayed. If the down switch 21 sticks closed when it should be open, a“brush up” error message will be displayed.

Buffer motor 31 is then energized, causing buffer 26 to begin buffing asthe machine continues its travel in reverse. The oil head 28 startsdispensing oil again when the machine reaches the first “reverse load”distance on the lane according to the selected oil pattern program. Themachine progressively down-shifts to lower speeds as it continues towardthe foul line. When the last reverse load of oil has been applied, theoil head 28 stops and parks. Once the machine reaches the foul line,drive motor 50 is deactivated, causing the machine to stop and awaitoperator attention to move it to the approach of the next lane.

If at any time during its travel up and down the lane machine 10 stopsand displays a “LOW BATTERY OR E-STOP PRESSED” warning, this meanseither battery voltage has dropped below seventeen volts or theemergency stop switch 117 (FIG. 13) has been pressed. In either case,the machine will need to be returned to the foul line and connected tothe 120 VAC house power supply for recharging or running on housecurrent using the electrical power supply cord.

The constant voltage regulator 128 plays a significant role in themachine 10 if it is battery-powered (there is no requirement that themachine functions as above described be incorporated intobattery-powered machines. However, significant ease-of-use benefits areachieved when they are.) Because the constant voltage regulator 128 iscapable of maintaining a constant voltage of twenty-four volts to thekey functions of the machine even though the batteries may run down totwenty or twenty-one volts, there is no gradual loss of performance. Themachine shows no signs of losing battery power until the voltage dropsso low (such as seventeen volts) that the controller 110 simply shutsdown and the machine stops and displays the warning. The dispensing headmotor 42, oil pump motor 33, buffer motor 31, three-way valve 35, anddrive motor 22 all operate from the constant voltage regulator 128.

The inventor(s) hereby state(s) his/their intent to rely on the Doctrineof Equivalents to determine and assess the reasonably fair scope ofhis/their invention as pertains to any apparatus not materiallydeparting from but outside the literal scope of the invention as set outin the following claims.

1. In a bowling lane maintenance machine adapted to travel in a forwarddirection along a bowling lane from the foul line to the pin deck andthen in a reverse direction from the pin deck to the foul line, theimprovement comprising: a drive motor operable to cause the machine totravel in the forward and reverse directions, a lane sensor operable todetermine the distance the machine has travelled along the lane, and acontrol system operably connected to the lane distance sensor and thedrive motor for controlling operation of the drive motor in response toinput signals from the lane distance sensor; a cleaning system includinga cleaning solution reservoir and liquid dispenser fluidically connectedto the cleaning solution reservoir and operable for delivering cleaningsolution to the lane, a vacuum suction head that is movable between araised position in which the head is spaced above the lane and a loweredposition in which the head is in operating contact with the lane forremoving cleaning liquid therefrom as the machine travels along thelane, and a squeegee assembly including at least one squeegee-type bladeand a squeegee lift motor operable for selectively moving the said atleast one squeegee-type between an operating position with thesqueegee-type blade in engagement in engagement with the lane and araised position out of engagement with the lane; said suction headcommunicating with a vacuum motor that draws a suction at the head whenthe motor is in an energized condition, said vacuum motor being in anenergized condition during at least most of the travel of the machine inthe forward direction and in a de-energized condition during at leastmost of the travel of the machine in the reverse direction, said controlsystem being operable to stop operation of said drive motor when thelane distance sensor determines that the machine has traveled in theforward direction from the foul line a distance which causes thesqueegee blade assembly to pass beyond and overhang the edge of the pindeck of the lane said control system being further operable for causingthe squeegee lift motor to move the squeegee assembly to a raisedposition when the lane sensor detects that the machine has stopped inits position overhanging the edge of the pin deck of the lane, for thenmaintaining the squeegee assembly raised as the drive motor causes themachine to move in the reverse direction for a predetermined distance,for then moving the squeegee assembly to a lowered position inengagement with the lane, for then causing the drive motor to move themachine in the forward direction with the squeegee assembly in theforward direction, and for then causing the drive motor to stop movementof the machine when the squeegee assembly passes beyond and overhangsthe edge of the pin deck of the lane for a second time.
 2. In a bowlinglane maintenance machine as claimed in claim 1, said vacuum motor beingin a de-energized condition when the machine is at the foul line beforecommencing travel in the forward direction, said vacuum motor beingenergized only after the machine has traveled a predetermined distancein the forward direction.
 3. In a bowling lane maintenance machine asclaimed in claim 1, said control system further being operable to movethe suction head to its raised position after the machine overhangs theedge of the pin deck of the lane for a second time and to maintain thesuction head raised and the vacuum motor de-energized as the machinereturns to the foul line in the reverse direction.
 4. In a bowling lanemaintenance machine adapted to travel in a forward direction along abowling lane from the foul line to the pin deck and then in a reversedirection from the pin deck to the foul line, the improvementcomprising: a cleaning system including a vacuum suction head that ismovable between a raised position in which the head is spaced above thelane and a lowered position in which the head is in operating contactwith the lane for removing cleaning liquid therefrom as the machinetravels along the lane, said suction head having a squeegee bladeassembly associated therewith; a drive motor operable to cause themachine to travel in the forward and reverse directions; a lane distancesensor operable to determine the distance the machine has traveled alongthe lane; and a control system operably connected to the lane distancesensor and the drive motor for controlling operation of the drive motorin response to input signals from the lane distance sensor, said controlsystem being operable to stop operation of said drive motor when thelane distance sensor determines that the machine has traveled in theforward direction from the foul line a distance which causes thesqueegee blade assembly to pass beyond and overhang the edge of the pindeck of the lane.
 5. In a bowling lane maintenance machine as claimed inclaim 4, said control system being operable to cause the suction head tomove to the raised position after the machine has stopped in itsposition overhanging the edge of the pin deck of the lane, then causethe suction head to remain raised as the machine moves in the reversedirection for a predetermined distance, then cause the suction head tomove to its lowered position, then cause the suction head to remainlowered as the machine moves in the forward direction, and then causethe drive motor to stop operation when the squeegee assembly passesbeyond and overhangs the edge of the pin deck of the lane for a secondtime.
 6. In a bowling lane maintenance machine as claimed in claim 5,said suction head communicating with a vacuum motor that draws a suctionat the head when the motor is in an energized condition, said controlsystem further being operable to move the suction head to its raisedposition after the machine overhangs the edge of the pin deck of thelane for a second time and to maintain the suction head raised and thevacuum motor de-energized as the machine returns to the foul line in thereverse direction.
 7. In a bowling lane maintenance machine as claimedin claim 6, said vacuum motor being in a de-energized condition when themachine is at the foul line before commencing travel in the forwarddirection, said vacuum motor being energized only after the machine hastraveled a predetermined distance in the forward direction.